Análisis de la contaminación por el parásito Toxoplasma gondii en el canal de riego Latacunga–Salcedo–Ambato, en el sector Izamba

Abstract

Toxoplasma gondii is a zoonotic parasite with a wide global distribution that poses a risk to public and veterinary health, causing catastrophic diseases such as toxoplasmosis. Its transmission through irrigation water constitutes a potential route of contamination for both crops and animals intended for human consumption. This study employed direct microscopy and PCR to analyze Toxoplasma gondii oocyst contamination in the Latacunga–Salcedo–Ambato (LSA) irrigation canal, in the Izamba sector. Microscopic results revealed a 45.73 percent contamination with oocysts compatible with Toxoplasma gondii, with a higher frequency in the localities of San Miguel Arcángel, San Francisco de Quillanloma, and Quillanloma la Playa. Physicochemical analyses of the water revealed that the presence of oocysts is not associated with water quality, but rather with factors such as local anthropogenic contamination. In contrast, the results of molecular identification targeting the B1 gene fragment did not detect the presence of Toxoplasma gondii genetic material due to inhibitors during PCR, caused by a mixed parasite load. The LSA canal did not show sufficient Toxoplasma gondii contamination to support the claim of a risk of transmission through irrigation water. However, the canal is a vital water infrastructure for the country's agricultural productivity, and its potential to act as an environmental reservoir for pathogenic parasites poses a threat to food safety, public health, and local veterinary health.